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token

Token
0xc4fc0da7c15e...3942d642c894
DAO ForkContract #24KExact Bytecode MatchEdit this contract
Deployed September 28, 2016 (10 years ago)Block 2,338,432

An ethereum.org tutorial token deployed with no name and no symbol, with a fixed supply, allowances and approveAndCall.

DAO Fork EraVerified Source

Historical Significance

This is the tutorial revision that added delegated spending, and it did it with approveAndCall: the allowance is set and the spender is called in the same transaction, so a contract learns about its allowance at the moment it is granted. It solved the problem ERC-20's plain approve leaves open, that a contract cannot notice an approval, and it was dropped from the standard anyway because it requires the spender to be a contract. The idea returned years later as ERC-777 and ERC-1363.

This deployment left the name and the symbol empty. Both are set once in the constructor and no function changes them, so the token has no display identity of any kind and never will: a wallet holding it can only ever show its address.

Context

By late 2016 ERC-20 had settled the interface a token was expected to answer, and the ethereum.org tutorial was still where most people copied one from. OpenZeppelin's contracts were not yet the default, so the code behind a token of this period is usually the tutorial's, with the constructor arguments changed and nothing else.

Token Information
Decimals
0
Key Facts
Deployment Block
2,338,432
Deployment Date
Sep 28, 2016, 01:23 AM
Code Size
3.0 KB
Gas at Deploy
960,264

Description

A fixed-supply token supporting transfers and third-party allowances, plus approvals that call back into the spending contract. Deployed September 2016 by 0x8bba7755e37421b75174bd531ff45b3a02332606.

Source Verified

Exact bytecode match(3,067 bytes)
Compiler: v0.4.0+

Historian Categories

Token
Heuristic Analysis

The following characteristics were detected through bytecode analysis and may not be accurate.

Detected Type: Token
Has ERC-20-like patterns

Bytecode Overview

Opcodes3,067
Unique Opcodes143
Jump Instructions126
Storage Operations40

External Links

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